DESCRIPTION (provided by investigator): Inappropriate use of antimicrobials in healthcare facilities results in serious public health consequences due to promotion of antimicrobial-resistant pathogens. Urinary tract infections (UTIs) account for a significant proportion of inappropriate antimicrobial use in acute care and long-term care settings because they are common and because treatment is often prescribed for asymptomatic bacteriuria (ASB), for which therapy is not indicated. In addition, many symptomatic UTIs are attributable to overuse of urinary catheters, and are therefore preventable. The central hypothesis of this proposal is that an algorithm-based intervention designed to prevent and appropriately manage UTI will safely decrease antimicrobial use and reduce rates of antimicrobial resistance in a healthcare system. The specific aims of this proposal are to: 1). determine the frequency of, reasons for, and adverse effects of inappropriate treatment of UTI in a tertiary care medical center and affiliated long-term care facilities and outpatient clinics;2). examine the effect of unnecessary antimicrobial treatment of ASB on colonization and dissemination of antimicrobial-resistant pathogens, including antimicrobial-resistant gram- negative bacilli, MRSA, and vancomycin-resistant Enterococcus;and 3). determine if an algorithm-based intervention for prevention and management of UTI, in combination with an intervention to decrease unnecessary use of fluoroquinolone antibiotics for other indications, will safely decrease fluoroquinolone and total antimicrobial use and reduce rates of antimicrobial resistance in a healthcare system. Fluoroquinolone antibiotics are commonly overused for other syndromes in addition to UTI. Therefore, combining the intervention for prevention and management of UTI with an intervention to decrease overuse of fluoroquinolones for other indications will maximize the potential to significantly reduce selective pressure exerted by these agents. The proposed studies will provide a model for healthcare facilities to prevent and appropriately manage UTIs and to reduce the development of antimicrobial-resistant infections.